I bought Birkenstocks in wide fitting when I was recovering from a major foot injury - so my foot still had some level of swelling. I tried them on recently and my foot was swimming in space. I'd say you need normal unless your feet are quite wide/pregnancy etc.

Just found this on their website:"If you want to check the width of a pair of Birkenstocks you already own, you can tell by inspecting the foot bed where there is a small image of a foot - if it's filled in the shoe is a narrow fitting, and if it's an outline it's regular."Hope it helps!

thank you iloveapples, i just have the outline so it must be regular fitting. and warmandwooly i will def try tk maxx first then. we have quite a small store so ours is a bit hit and miss, but worth a go!